Expectations

Studies suggest that typical code gets shipped with 0.5 to 1% defect
rate. That is, the code in a 100KLOC product probably has 500 to 1000
bugs. Yes, some organizations do very much better, but the norm is just
not acceptable.

There are many reasons for poor quality. One is management
expectations. Software engineering is viewed as an intrinsically
chaotic process with unpredictable and non-repeatable results. The boss
and sales department are so exhausted by the development process that
when the product finally appears they're happy to ship, no matter what
problems still lurk.

Software engineering is indeed hard. But it doesn't have to be
either chaotic or unpredictable. If management doesn't hold engineers
to high standards, if they don't routinely expect products to be done
correctly, odds are they won't.

Engineers should be expected to deliver high quality, well-tested,
maintainable code.

The corollary, of course, is that engineers should expect adequate
resources from management, be they personal, tools, requirements and
time.

Users of the SPARK language, for
instance, have reported incredibly low bug rates, in some cases zero on
delivery of a product. That's due to several reasons including the use
of a safe language (it's a subset of Ada) with tools that do formal
proof checks against annotations provide in the comments.

Those tools are important, but success in SPARK comes from an
expectation that developers will use them correctly and all of the
time. Shortcuts aren't allowed. There are no exceptions. C
developers can benefit from the same philosophy.

Yet in too many outfits bugs are considered normal.

Perfection is impossible in any human endeavor, so bugs will occur.
But this is the only industry on the planet where companies can deliver
products full of known defects and not get sued. Someday no one will
smoke and all of the asbestos will be buried. Who do you think the
lawyers will go after?

Jack G. Ganssle is a lecturer and consultant on embedded
development issues. He conducts seminars on embedded systems and helps
companies with their embedded challenges. Contact him at jack@ganssle.com. His website is www.ganssle.com.